1. Field of the Invention
The present invention relates to endoscopic surgical methods and devices, and more specifically to methods and apparatus for manipulation of suture during endoscopic surgical procedures.
2. Description of the Related Art
Endoscopic suturing techniques and instruments have been developed in order to facilitate the suturing of tissue during endoscopic surgical procedures. The term "endoscopy" encompasses arthroscopy, laparoscopy, hysteroscopy, etc., and endoscopic surgery involves the performance of surgical procedures within a patient's body through small openings as opposed to conventional open surgery through large incisions. Access to a surgical work site within a patient's body is normally provided through one or more portals formed directly in the patient's body or through one or more cannulas inserted into the patient's body through small incisions. A chosen surgical procedure is carried out by a surgeon through the use of elongated instruments inserted through these cannulas and it often becomes necessary to suture selected tissue at the surgical work site.
Since the work site is only accessible through a small portal or cannula and since it is very difficult to tie sutures within the body, various devices and techniques have been developed to enable the surgeon to tie sutures endoscopically. For example, some procedures enable the surgeon to pass suture material through selected tissue, form a surgical knot extracorporeally and then move the knot with a knot pusher through the portal or cannula into position adjacent the desired tissue to be sutured. Some instruments used to pass the suture incorporate a hollow needle provided with some means, often a wire loop, to guide suture through the tissue pierced by the needle.